Pierre Auger Observatory

Pierre Auger Observatory

Control building in Malargüe
Named after	Pierre Victor Auger
Location(s)	Malargüe Province of Mendoza, Argentina
Coordinates	35°12′24″S 69°18′57″W / 35.20667°S 69.31583°W / -35.20667; -69.31583
Organization	Multi-national
Observatory code	I47
Altitude	1330 m–1620 m, average ~1400 m
Wavelength	330–380 nm UV (Fluorescence detector), 1017–1021 eV cosmic rays (Surface detector)
Built	2004–2008 (and taking data during construction)
Telescope style	Hybrid (Surface + Fluorescence detectors)
Website	Official site
Location of Pierre Auger Observatory
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[edit on Wikidata]

The Pierre Auger Observatory is an international cosmic ray observatory in Argentina designed to detect ultra-high-energy cosmic rays: sub-atomic particles traveling nearly at the speed of light and each with energies beyond 10¹⁸ eV. In Earth's atmosphere such particles interact with air nuclei and produce various other particles. These effect particles (called an "air shower") can be detected and measured. But since these high energy particles have an estimated arrival rate of just 1 per km² per century, the Auger Observatory has created a detection area of 3,000 km² (1,200 sq mi)—the size of Rhode Island, or Luxembourg—in order to record a large number of these events. It is located in the western Mendoza Province, Argentina, near the Andes.

Construction began in 2000,^[1] the observatory has been taking production-grade data since 2005 and was officially completed in 2008. The northern site was to be located in southeastern Colorado, United States and hosted by Lamar Community College. It also was to consist of water-Cherenkov detectors and fluorescence telescopes, covering the area of 10,370 km²—3.3 times larger than Auger South.

The observatory was named after the French physicist Pierre Victor Auger. The project was proposed by Jim Cronin and Alan Watson in 1992. Today, more than 500 physicists from nearly 100 institutions around the world^[2] are collaborating to maintain and upgrade the site in Argentina and collect and analyse the measured data. The 15 participating countries shared the $50 million construction budget, each providing a small portion of the total cost.